Process for the production of intaglio printing-surfaces for lithographic or aluminum printing.



w. J. R. BARTLETT. I PROCESS FOR THE PRODUCTION OF INTAGLId PRINTING SURFACES FOB. LITHOGRAPHIG 0R ALUMINUM PRINTING.

APPLICATION FILED JAN. 2, 1908.

1,038,266. Patented Sept. 10, 1912.

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WALTER J. R. BARTLETT, OF SAN FRANCISCO, CALIFORNIA.

PROCESS FOR THE PRODUCTION OF INTAGLIO PRINTING-SURFACES FOR LITHO- GRAPHIC OR ALUMINUM PRINTING.

Specification of Letters Patent.

Application filed January 2, 1908. Serial No. 409,083.

' ful Improvements in Processes for the Pro duction of Intaglio Printing-Surfaces for Lithographic or Aluminum Printing, of which the following is a specification.

My invention relates to improvements in printing processes and consists of a process whereby duplicate intaglio engravings may be produced in intaglio in zinc or aluminum plates, adapted for printing from lithographic or aluminum presses by lithographic printing methods.

My invention comprises the novel steps and methods set forth in the claims.

The accompanying drawings show the conditions of a plate in the various steps of my process.

Figure 1 is a face view of a plate having an intaglio design impressed therein. Fig. 2 is a section of the same plate after being coated with the protective film. Fig. 3 is a similar section after the film has been polished or ground off down to the plane surface of the plate. Fig. 4 is a section of the finished plate.

The general steps of my invention are as follows: First, it is required to produce a cameo of an original engraving on a hardened steel plate. This cameo impression of the original is raised to the requisite height on a steel plate which is afterward hardened. The method then employed is similar to that in operation at present for procuring duplicate intaglio engravings on steel plates. The cameo impression B is sunk into a plate Aof zinc or aluminum to the required depth as many times as desired, thereby causing the zinc or aluminum plates to be covered with indented or intaglio impressions of the original cameo engraving. After these duplicate cameo impressions have been made in the plate to the desired extent, the plate is entirely covered with a film C of acid-resisting material capable of being hardened by the action of actinic rays. The preferred composition for this film is as follows: purified bitumen, 50 cc., benzole, 250 cc., chloroform, 100 cc., Venice turpentine, 5 cc. This film is flowed over the zinc or aluminum plate, completely covering its surface, including the int-aglio indentations made by the original cameo. The film covered plate is then exposed to the action of actinic rays, which hardens the film surface. After this hardening action has proceeded as far as necessary, the plate is polished with a piece of fiat charcoal or other suitable substance, whereby the main body of the plate surface is exposed, but leaving the depressed indentations or cameo impressions, filled with the film matter C up to the height of the plate surface. This covering C of bitumen, occupying the in- Patented Sept. 10, 1912.

dented designs in the plate, acts as an acid resist to any mordant or chemical which may be applied to the exposed surface of the zinc or aluminum plate in order to prepare the plate for lithographic or aluminum printing purposes. After the surface of the zinc or aluminum platehas been subjected to the treatment required, it will be found necessary, in order to produce intaglio printing results, to remove the hardened film covering the depressed surfaces or indentations caused by' the original cameo.

This is done by flowing over the plate a solventv like chloroform, which completely removes the bitumen without destroying the effect by the etching thereof for lithographic or aluminum printing purposesthat is, without destroying the effect .of the etching process in making the plane surface of the plate ink-repellent, and at the same time the depressed int-aglios, having been protected from such action by the bitumen film. are thereby capable of being sensitive for the retention'and to the action of ink. The

a covering of lithographic ink, whereby the portions of the plate that were protected from the lithographic etching treatment by the film covering of bitumen, i. e., the depressed intaglios, retain the ink, while the surfaces of the plate acted on by the etching materials are not affected thereby. The plate may then be used to print from by lithographic or aluminum printing methods.

Any acid-resisting film or substance may be employed as acovering for the depressed or intaglio portions of the plate before being polished by the charcoal. The film which I prefer is the one whose composition gas been before given, having a bitumen ass;

produced upon the surface of the plate zinc or aluminum plate is then subjected to called lithographic intaglio printing.

A distinctive feature of my invention is the production of intaglio printing surfaces on metals, metal compositions or substances capable of being manipulated on lithographic or aluminum presses, whereby greater speed is obtained as contrasted wit the present slow methods employed in printlng from copper or steel plate intaglios, where the plates require mechanical wiping off for each impression. In lithographic and aluminum printing methods no such wiping of the plates is required, which permits speed, and the resulting printing from intaglios in zinc and aluminum plates will have the raised effect combined with the greater speed. By the film of bitumen being dissolved or Washed out of the depressed being on a level with the exposed surfaces of the plate, thus protecting the intaglio designs from the etching processes, then cleaning the remaining film from the plate by using chloroform without afiecting the chemical action on the plate surface caused by the etching manipulations, and alsowithout affecting the ink-sensitiveness of the depressed surfaces formerly covered by the bitumen film.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. The herein described process for the production of intaglio print-mg surfaces on zinc or aluminum, which consists in pressing a hardened cameo from an original engraved surface into a plate of zinc or aluminum, then covering said plate with a film of acid-resistant material capable of being hardened by the actinic action of light,

hardening said film by exposure to actinic rays, polishing the plate with charcoal or other suitable material, etching the plate surfaces thus exposed by lithographic or aluminum etching methods, dissolving out the film left in the intaglio design by the solvent action of chloroform or other suitable solvent, whereby the intaglio design may be used as an ink-retaining surface from which to print.

2. The herein process forproducing duplicate printing surfaces from an original engraving which-consists in sinking a bardened cameo copy of the original engraving int-o the surface of a plate adapted for printing by lithographic or aluminum processes, covering said plate with a filrn'of material of an acid-resisting character, drying the same, then polishing the film covered surface with charcoal or other suitable material, thereby exposing the plane surface of said plate without removing the film from the depressed portions thereof, then etching the exposed surfaces of the plate with chemicals suited to lithographic or aluminum printing processes, then using a suitable solvent, as chloroform, or benzole, to clear off the acid-resistant film covering the depressed portions of the plate.

3. The herein described process for the production of intaglio printing surfaces adapted for use under lithographic or aluminum printing conditions, which consists in producing the design in intaglio in a plate having normally ink-attractive qualities,

protecting said intaglio designs by a coating or film, treating the plane surface of the plate wi h an etching fluid to render the same i k-repellent without coating the material of which it is composed, and then removing the protective film from the intaglio design; thereby producing an uncoated plate with design and non-design surfaces having opposite ink-receiving qualities.

In testimony whereof, I have hereunto af- -fixed my signature this 11th day of Dec.

1907, in the presence of two witnesses.

WALTER J. R. BARTLETT. Witnesses:

R. R. Ronnn'rson,

L. E. SEXTON. 

